@hajra Welcome to Mayo Clinic Connect. What has led you here?

We need to live and look towards what we want to achieve today, and in long-range plans. Thinking that we have only a limited time to accomplish anything will bring tension, more anxiety. Maybe even make us forego relationships or chances on a day-to-day basis. Dwelling on negative/anxiety provoking things can seem to make them multiply, never a good thing in my opinion!

As @mir123 mentioned, taking as good care of ourselves physically/ emotionally/mentally as we can, will go a long way to easing the "what ifs" of life. Becoming a doctor is a noble idea. How far along in your studies, are you?
Ginger